Help Characters missing from Screen

[DavidWMurray]

Hi,
I've searched the forums for this issue but I'm unable to find anyone having the same problem, so my apologies in advance if this is a duplication.
The problem is with my wife's HTC One M9 Smartphone. The screen has developed a weird problem of failing to display all the characters in any text on any application so that you end up trying to best guess what it says.
I've tried doing a factory reset in an attempt to resolve it but with no success as the problem still exists after it rebooted.
This suggests to me (with my limited knowledge) that this is more likely to be a hardware issue rather than software but I don't know if it's a processor problem or LCD screen.
Has anyone come across this kind of issue before and, if so, can you suggest what the cause is and is there a solution other than throwing the phone away.
David

 

[Hadron]

Hardware might cause a problem with displaying /anything/ on part of the screen, but it won't specifically affect text characters. So software sounds more likely. Have you modified the software in any way (e.g. rooted it), or had a system update before this started?

Is it specific characters that don't display, e.g. no "e"s? That could happen if the system font had somehow been corrupted. Recent HTC's allow you to change fonts as part of the Personalize settings, so have you tried doing that and seeing whether it fixes this? That would be the simplest solution if so.

All that a factory reset does is delete user-installed apps and data, so if somehow something has happened to the system software a reset will do nothing to fix that. So another thing you can try is reflashing the phone software. To find the right software we'll need to know your "cidnum", but if you can tell us what country the phone was originally sold in and whether it was bought through a carrier (and if so, which) we can probably work that out (otherwise you'll need to install some software on a computer to find out). Any information about software version would also help. If you can't read that from the settings (because of this problem) you could try rebooting while pressing the volume down key and tell us what it says on the bootloader screen (which that procedure will take you to). If characters display correctly on that screen it will be a further indication that its a software issue.

All of this assumes you've not rooted or otherwise modified the software. If you have then let us know, as that could suggest other causes/solutions.